Clinical Approach to the Patient with a Possible Tick-Borne Illness

Abstract

There are many challenges in the clinical recognition, management, and treatment of patients with tick-borne diseases. The first and most important step for clinicians is to simply consider the possibility of a tick-borne infection in patients who, through their place of residence, occupational or recreational activities, or travels, may have been exposed to ticks that are vectors of human disease. In such a setting, considering the possibility of a tick-transmitted disease is critical because the disease manifestations are often both nonspecific and multisystemic, there are seldom definitive clinical or laboratory diagnostic findings present at the time of presentation, and the consequences of failure to treat can be fatal. As a result, prompt presumptive therapy is often appropriate and may, in fact, be lifesaving. This chapter provides an overview of differential diagnosis and points to consider related to certain clinical and laboratory manifestations of disease as well as empiric treatment. In addition to known tick exposure or bites in areas of endemicity, clinical findings particularly suggestive of a possible tick-borne infection may include leukopenia and/or thrombocytopenia and persistent fevers despite use of broad-spectrum antimicrobials, as well as negative routine cultures and the presence of otherwise unexplained skin rashes or lesions (particularly if petechial, hemorrhagic, or eschar) or central nervous system abnormalities.